金屬玻璃擁有高強度、高硬度、耐磨性及耐腐蝕性等特點，屬於潛在的先進結構材料。然而金屬玻璃在室溫下較差的拉伸延展性，容易產生剪切帶，導致金屬玻璃容易出現破裂的行為，在應用上被大大的限制住。
本研究利用介觀尺度的模型，結合動力學蒙地卡羅(kinetic Monte Carlo, kMC)以及相場微彈性理論(phase-field micro-elasticity theory)等理論來執行計算。第一階段係從殘留應力與軟化因子切入，探討這兩個變因對金屬玻璃機械性質的影響。先針對殘留應力值大小對塊材的機械性質的影響進行討論，再進一步討論殘留應力分佈情形對其影響；接著改變軟化因子，找出能影響剪切帶走向的幾組軟化因子值。
第二階段則是引入複材模型，利用奈米玻璃的型式來改善金屬玻璃的機械性質。奈米玻璃的結構與金屬玻璃類似，只是其組成顆粒奈米化，而微觀結構來看，奈米玻璃結構中，存在精細的玻璃介面，此玻璃介面的彈性模數與原材料有些許不同，因此本研究將模型改成複材模型，觀察剪切帶在交界面上的走向會如何改變。
最後，模型透過拉伸過後對應之應力的平均值、標準差及分佈，有系統地整理歸納出金屬玻璃中的變形行為及剪切帶的走向變化。研究結果指出，藉由施加適合的殘留應力值與適當的分布，可以使變形中的剪應變軟化效果減緩；也可以透過複材形式模擬奈米玻璃，其玻璃介面可阻擋剪切帶的延伸，進而增加材料的延展性。

In this study, the mesoscopic model combines kinetic Monte Carlo (kMC) and phase-field microelasticity theory to proceed with the calculation. In the first stage, the effects of residual stresses and softening factors on the mechanical properties of metallic glass were investigated. In the second stage, a composite model is introduced to improve the mechanical properties of metallic glass by adding the nanoglass. The structure of the nanoglass is similar to the metallic glass, but the constituent particles of nanoglass are nanostructured and sepa-rated by a fine glass interface. The elastic modulus of the glass interface is slightly different from that of the raw material. Through the composite model, one can observe the direction of the shear band changes due to the interface of the nanoglass.
The results show that the shear strain softening effect can be reduced by applying ap-propriate residual stress and proper distribution. In addition, the adding of nanoglass can block the extension of shear band.

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